"Marine boot camp" has a mystical aura attached to it. It features in ad campaigns and in reality programmes, is described as a rite of passage and a test of manhood and is seen as a cure for everything from a sulky teenager to a flabby gut. So it was interesting to be invited, as part of a group of 28 other foreign journalists, to see inside one such boot camp in San Diego last week.

Marines regard themselves as something of a cut above the soldiers and sailors in the military, not least because their training is longer - 12 weeks compared to, say, six weeks for the navy. They quote their history and their slogan - "once a marine, always a marine" - and explain that when it comes to war, as it soon may, they are "first in". (A friend who was in the US Rangers disputes this, saying it is not marines but Rangers or Navy Seals who go in first, but we'll let that pass.)

What was fascinating was looking at the raw recruits - young men with baggy trousers, basketball shirts and long hair - and realising that within 12 weeks they would have lost their puppy fat and their haircuts and become one of the shaven-headed young men we saw being yelled at around the parade ground.

What was also interesting was to find out how speedy the turnover of marines was. Most - 70% - enter only for four years after which they can leave, pick up $36,000 (£22,000) in college fees or parlay themselves a job on civvie street with their newly acquired skills as a jeep repairman or radio operator. Foreigners can join and some do so, as a swift way to qualify for citizenship; among the foreign intake, we were told, was the son of a Somalian warlord.

We watched a bunch of would-be recruits going off for blood tests for drugs and HIV and here the marines seem to have a more forgiving policy than that of the US government. If a would-be recruit has marijuana in his bloodstream, he can come back after 45 days and have another go. If he still has traces, he can try again in a year's time; for cocaine, there had to be a gap of a year before the recruit could try again and then two years, if there were still traces.

Now the US government has been running commercials over the last few months in which people who use drugs are accused of aiding terrorism, on the grounds that money from drugs supposedly ends up with terrorists.

These ads last month prompted an entertaining series of satires in which drivers of SUVs (sport utility vehicles) were accused of aiding terrorists because they consumed so much gas. Either the government is unwittingly recruiting people who have assisted terrorists or it is engaged in a very cynical and hypocritical ad campaign.

One of the journalists said the whole boot camp process reminded her of a feature she had done on young men becoming monks: shaved heads, abstinence, early mornings, vows and chants, albeit ones like "Up in the morning with the California sun! We're going to run all day till the running's done!"

Certainly there was something monastic about it all, with 50 sleeping in a room, reminding me of the old John Prine song, Donald and Lydia, in which he sings of a barracks as "a warehouse of strangers with 60-watt lights".

We were issued with a handy fact sheet about the average recruit, who is 160 pounds in weight, mainly Protestant (53%), or Catholic (30%) with 13 per cent "no preference". It was also good to know that by the end of training they would have consumed 336,000 calories. The whole facility is dotted with bracing signs such as "every job is a self-portrait of those who do it. Autograph your work with quality."

Iraq, of course, hovered over the proceedings like one of those buzzards that cruise so casually along the cliffs of the southern Californian coast. Most of the young men - 5% of the recruits are women but they were trained elsewhere - we spoke to had little knowledge of the latest situation since they are allowed no radio or television and were too tired to read a paper on the one day, Sunday, when that was permitted.

We saw the finished products, too, as they passed out at the end of their 12 weeks. What was striking was how young they all looked and one could not help but think of other shaven-headed young teenagers who presumably right now are being shouted at by the Iraqi equivalent of a drill instructor but who, one feels, will not be singing "Up in the morning with the Baghdad sun!"

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